So if you have a dog as an ESA, where do you go from then on? Certification is the best step forward. However, remember, there is no legal institute or a way of certifying your ESA. Those who may try to scam you would use this as their purpose. There is no need for certifying an ESA dog but there is one essential element that should be with you at all times and that is an ESA letter. So, what value does it hold and how you get it? Well, let’s see.